NEW METHODOLOGIES FOR KINETIC-STUDY OF 5-(HYDROXYMETHYL)-FURFURAL FORMATION AND REACTIVE LYSINE BLOCKAGE IN HEAT-TREATED MILK AND MODEL SYSTEMS

New analytical techniques were used to study the kinetic behavior of 5-(hydroxmethyl) furfural (HMF) and blockage of available lysine in milk and model systems. Both determination of HMF by the chromatographic method and estimation of available lysine by the orthophthaldialdehyde (OPA) method at sterilization temperatures proved valid. Activation energies for the lysine loss reaction were 91.14, 112.41 and 66.67 kJ.mol-1 in the model systems and the milk respectively in fluorimetric determination with OPA. Activation energy for HMF determination ranged from 118.5 to 93.04 kJ.mol-1.